Troubleshooting the 11 Most Common Film Related Problems with a VFFS

Editor's Note: This resource was first published in March of 2017 but is frequently updated with new relevant information.

When your packaging line goes down at 2 AM, you need answers fast. Here's your field guide to the most common VFFS film issues and how to resolve them.

Why Is VFFS Troubleshooting Information So Hard to Find Online?

Information for almost any subject is available instantly. Pull out your phone, type a question, and get immediate answers. But if you're managing a packaging operation and your VFFS machine starts acting up, you'll quickly discover this is one area where helpful online resources are surprisingly scarce.

Picture this: You're overseeing third shift operations when film tracking goes wrong on your vertical form-fill-seal line. You search "Why is my film not tracking on VFFS?" and find nothing but ads and generic brochures. Meanwhile, your line stays down and costs pile up.

No operation can afford extended unplanned downtime. Every minute of disruption wastes resources, delays shipments, and impacts your bottom line. Quick problem identification prevents minor issues from becoming major production disasters.

What Are the Most Common VFFS Film Problems That Cause Downtime?

Drawing from decades of field experience with Rovema machines, Allen Overmyer has identified the 11 most frequent film-related issues that disrupt  Vertical Form Fill Seal machine operations. These problems account for the majority of unscheduled maintenance calls and emergency troubleshooting requests.

The 11 dilemmas we're looking to solve in this vffs troubleshooting article:

1. Film runs off-center
2. Film will not track
3. Film feed belts will not move
4. Bag Length is inconsistent
5. Bag Length is too long
6. Creases in film
7. Film Unwind is Difficult
8. Pulling film down the forming tube is difficult
9. Film jams at the forming tube
10. Film feed belts are slipping
    
11. Film is Sticking to the Vertical Seal

How Do You Fix Film That Runs Off-Center?

Problem: Film consistently drifts to one side during operation, causing alignment issues and potential seal problems.

Root Causes to Check:

• Roll of film is not centered on the film carriage or the spindle
• Film roll is improperly wound
• Film roll is loose on the spindle
• Belts are misaligned to the tube

Quick Fix: Start with spindle centering—this resolves 80% of off-center film issues. If the problem persists after centering, inspect the film roll quality and belt alignment.

Why Won't My Film Track Properly on the VFFS?

Problem: Film wanders or shifts position unpredictably during operation, making consistent bag formation impossible.

Root Causes to Check:

• The roll is not centered on spindle.
• Spindle is loose
• Film is not properly threaded on carriage

Quick Fix: Re-thread the film following your machine's threading diagram. Loose spindle mounting is often overlooked but frequently causes tracking issues.

What Causes Film Feed Belts to Stop Moving?

Problem: Feed belts fail to advance film, stopping production completely.

Root Causes to Check:

• Check to see if belts are too tight against tube
• Check the film drive gear boxes and couplings
• Check the cables and drive for the film feed motor
• Check the bearings in the belt drive shaft

Quick Fix: Check belt tension first- overtightening is the most common cause. If belts move freely by hand but won't engage, inspect the drive system.

How Do You Solve Inconsistent Bag Length Problems?

Problem: Finished bags vary in length, creating issues with case packing and product presentation.

Root Causes to Check:

• Film is not threaded properly
• Film feed belt tension is improperly adjusted
• Film feed belts need to be cleaned

Quick Fix: Clean the feed belts first—buildup from film additives or environmental contamination frequently causes slippage that leads to length variation.

Why Are My Bags Coming Out Too Long?

Problem: All bags exceed the target length consistently.

Root Causes to Check:

• Bag length is incorrectly set
• Reset bag length in control display
• Registration photo eye is not set correctly

Quick Fix: Verify the bag length setting in your control system matches your product requirements. Registration eye misalignment can add unexpected length to each bag.

What Causes Film Creasing During Operation?

Problem: Wrinkles or creases appear in the film, affecting bag appearance and potentially compromising seal integrity.

Root Causes to Check:

• Forming collar is worn out
• Forming collar is improperly adjusted
• Setup roller is improperly adjusted
• Valve is stuck on the forming collar, or rollers
• Contaminated roller in the film path
• Obstruction on the forming collar from printer

Quick Fix: Inspect the forming collar first, wear patterns are usually visible. Clean all contact surfaces before making adjustments.

How Do You Fix Difficult Film Unwind Issues?

Problem: Film resists unwinding from the roll, requiring excessive force and potentially causing web breaks.

Root Causes to Check:

• Forming part is dirty
• Film co-efficient of friction is too high
• Check guide rollers for foreign materials and free movement
• Zipper caught in collar
• Contact pressure of the belts too high
• Forming tube out of alignment

Quick Fix: Clean the forming tube and collar assembly. Many unwind issues stem from film additive buildup that increases friction.

What Makes Film Hard to Pull Through the Forming Tube?

Problem: Excessive resistance when film moves through the forming section, potentially causing web breaks or stoppages.

Root Causes to Check:

• Forming set is dirty
• Film co-efficient of friction is too high
• Splice tape is caught in the collar
• Check the guide rollers for foreign materials and free movement
• Forming collar is not aligned properly to the tube
• Contact pressure of the belts is too high
• Setup rollers are out of alignment

Quick Fix: Start with a thorough cleaning of the forming set. Check for splice tape remnants—they're easy to miss but cause significant drag.

How Do You Clear Film Jams at the Forming Tube?

Problem: Film bunches up or jams at the forming tube entrance, stopping production.

Root Causes to Check:

• Vertical seal too hot, causing film to stick
• Too much pressure on the vertical seal band
• Film co-efficient of friction is too high
• If producing a stabilo bag, the seal is misaligned or too hot

Quick Fix: Reduce vertical seal temperature and pressure. Film sticking to hot sealing surfaces is the primary cause of forming tube jams.

Dilemma #10: Film feed belts are slipping

Problem: Belts can't maintain grip on the film, causing irregular feed and bag length variation.

Root Causes to Check:

• Not enough pressure on the film feed belts
• Belts are dirty
• Belts are worn
• Belts are misaligned to the tube
• Vacuum filter, or hoses, are clogged.
• Vacuum is turned off
• Film is not properly threaded

Quick Fix: Clean the belts and check vacuum operation. Many slipping issues are resolved by removing film additive buildup and ensuring proper vacuum assist.

How Do You Stop Film From Sticking to the Vertical Seal?

Problem: Film adheres to the vertical sealing band, causing web breaks or poor seal quality.

Root Causes to Check:

• Heat is too high
• Too much pressure
• Vertical seal  or cross sealing jaws need cleaning
• Film is misaligned to expose the sealant material inside the bag to the heated seal band

Quick Fix: Reduce temperature and pressure settings. Clean sealing surfaces to remove any film buildup that increases sticking tendency.

What Should You Know About Film Changes and Machine Performance?

Film structure changes can dramatically affect machine performance, even when the supplier reports "equivalent characteristics." A film that ran perfectly last month might cause multiple issues after a supplier reformulation or manufacturing change.

Communication between procurement, operations, and machine operators prevents confusion when performance suddenly changes after a roll change. Document any film specification changes and adjust machine settings accordingly.

When Should You Consider Equipment Replacement Instead of Troubleshooting?

Most of the issues covered here require minor adjustments, cleaning, or small parts replacement. But if you're fighting these problems consistently, there might be a larger equipment issue.

Frequent troubleshooting indicates:

• Worn machine components that need replacement
• Equipment that's undersized for your current production demands
• Technology gaps that newer machines could eliminate

Modern VFFS machines include features like automatic tension control, servo-driven adjustments, and predictive maintenance alerts that prevent many of these common problems.

Need More Than Troubleshooting Tips?

While preventive maintenance and quick troubleshooting keep your current equipment running, persistent issues signal it might be time for a conversation about upgrading your packaging capabilities.

If you're spending more time troubleshooting than producing, or if these issues are impacting your ability to meet customer commitments, we'd be glad to discuss how modern packaging technology could improve your operations.

Ready to move beyond constant troubleshooting? Contact our team to explore packaging solutions built for reliability, not just speed.